U.S. patent application number 10/780614 was filed with the patent office on 2004-08-26 for dental handpiece, torque applying tool for use therewith and dental kit including same.
Invention is credited to Cohen, Yechiel.
Application Number | 20040166473 10/780614 |
Document ID | / |
Family ID | 30012029 |
Filed Date | 2004-08-26 |
United States Patent
Application |
20040166473 |
Kind Code |
A1 |
Cohen, Yechiel |
August 26, 2004 |
Dental handpiece, torque applying tool for use therewith and dental
kit including same
Abstract
A dental handpiece including a housing of a size and
configuration to be conveniently graspable by a user; a dental tool
clamping device carried by the housing; a dental tool to be clamped
in the clamping device; a rotary drive for rotating the clamping
device, and the dental tool when clamped therein; and a
transmission system coupling the rotary drive to the dental tool to
rotate same. The dental tool includes a driving tip for engaging
the head of a fastening member to be fixed by rotation within the
patient's mouth. The transmission system includes a torque limiter
for limiting the torque applied by the rotary drive to the driving
tip. In some described embodiments, the torque limiter is included
within the dental housing, and in other described embodiments it is
included within the dental tool.
Inventors: |
Cohen, Yechiel; (Carmiel,
IL) |
Correspondence
Address: |
G.E. EHRLICH (1995) LTD.
c/o ANTHONY CASTORINA
SUITE 207
2001 JEFFERSON DAVIS HIGHWAY
ARLINGTON
VA
22202
US
|
Family ID: |
30012029 |
Appl. No.: |
10/780614 |
Filed: |
February 19, 2004 |
Current U.S.
Class: |
433/105 |
Current CPC
Class: |
A61C 1/145 20130101;
A61C 1/185 20130101; A61C 1/186 20130101 |
Class at
Publication: |
433/105 |
International
Class: |
A61C 003/03 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 20, 2003 |
IL |
154561 |
Claims
What is claimed is:
1. A dental handpiece, comprising: a housing of a size and
configuration to be conveniently graspable by a user; a dental tool
clamping device carried by said housing; a dental tool to be
clamped in said clamping device, said dental tool being of a size
and configuration enabling it to be received in the mouth of the
patient and used for performing an operation therein involved in a
dental treatment of the patient; a rotary drive for rotating said
clamping device, and the dental tool when clamped therein; and a
transmission system coupling said rotary drive to said dental tool
to rotate same; characterized in that said dental tool includes a
driving tip for engaging the head of a fastening member to be fixed
by rotation within the patient's mouth; and in that said
transmission system includes a torque limiter for limiting the
torque applied by said rotary drive to said driving tip.
2. The dental handpiece according to claim 1, wherein said torque
limiter is included within said housing between said rotary drive
and said dental tool clamping device.
3. The dental handpiece according to claim 1, wherein said dental
tool further includes a mounting shaft at the opposite end with
respect to said driving tip receivable within said clamping device
and releasably clampable therein.
4. The dental handpiece according to claim 3, wherein said torque
limiter is included within said dental tool between said mounting
shaft and said driving tip.
5. The dental handpiece according to claim 1, wherein said torque
limiter is presettable to limit the torque to be transmitted by
said rotary drive to said dental tool clamping device.
6. The dental handpiece according to claim 1, wherein said torque
limiter is a bellevielle-spring type overload coupling.
7. The dental handpiece according to claim 1, wherein said torque
limiter is a coil-spring type overload coupling.
8. The dental handpiece according to claim 1, wherein said torque
limiter is a torsion-bar type overload coupling.
9. The dental handpiece according to claim 1, wherein said rotary
drive is an electrical motor drive.
10. The dental handpiece according to claim 9, wherein said torque
limiter interrupts the electrical circuit to said motor drive when
the applied torque exceeds a predetermined value.
11. The dental handpiece according to claim 1, wherein said rotary
drive is a manual drive.
12. The dental handpiece according to claim 1, wherein said dental
handpiece further comprises a light source and an optical fiber
having one end adjacent to said light source and an opposite end
located to illuminate the region of the patient's mouth at which
said operation is to be performed when the dental tool is received
within the patient's mouth.
13. A tool for mounting to a housing including a rotary drive,
comprising: a driving tip at one end of the tool for engaging the
head of a fastening member to be fastened by rotation; a mounting
shaft at the opposite end of the tool for mounting to a housing
including a rotary drive; and a torque limiter between said driving
tip and said mounting shaft for limiting the torque to be applied
by said rotary drive to said driving tip.
14. The tool according to claim 13, wherein said driving tip is
sized and configured for enabling it to be received in the mouth of
a patient and used for engaging the head of a fastening member to
be fixed by rotation in the patient's mouth.
15. The tool according to claim 14, wherein said torque limiter is
presettable to limit the torque to be transmitted by said rotary
drive to said driving tip.
16. The tool according to claim 14, wherein said torque limiter is
a bellevielle-spring type overload coupling.
17. The tool according to claim 14, wherein said torque limiter is
a coil-spring type overload coupling.
18. The tool according to claim 14, wherein said torque limiter is
a torsion-bar type overload coupling which actuates an electrical
switch when a maximum torque is exceeded.
19. A dental kit comprising: a housing of a size and configuration
to be conveniently grasped by a user; a rotary drive within said
housing; a dental tool clamping device carried by said housing and
coupled to said rotary drive; and a plurality of different dental
tools selectively mountable in said dental tool clamping device for
use in various dental treatments of the patient; at least one of
said dental tools including a driving tip for engaging the head of
a fastening member to be fixed by rotation within the patient's
mouth; and a torque limiter for limiting the torque applied by said
rotary drive to said driving tip.
20. The dental kit according to claim 19, wherein said torque
limiter is presettable to limit the torque to be transmitted by
said rotary drive to said driving tip.
Description
FIELD AND BACKGROUND OF THE INVENTION
[0001] The present invention relates to a dental handpiece for use
in fastening members within a patient's mouth. The invention also
relates to a torque applying tool for use in such a dental
handpiece, and further, to a dental kit including such a dental
handpiece and toque applying tool.
[0002] Prosthetics, braces, and other dental devices frequently
include fastening members to be fixed by rotation within the
patient's mouth. At the present time, this is usually done manually
by using hand-held Allen keys, screwdrivers, spanners, or the like,
which are manually applied to the fastening member and then
manually rotated. Fixing fastening members within a patient's mouth
in this manner can be particularly awkward and time consuming. In
addition, if extreme care is not exercised, excess torque may be
inadvertently applied which could result in substantial damage to
the patient.
OBJECTS AND BRIEF SUMMARY OF THE PRESENT INVENTION
[0003] An object of the present invention is to provide a dental
handpiece which can be used for fixing fastening members within a
patient's mouth in a manner which is more convenient and less time
consuming to the dentist, and which avoids the danger of damage by
the application of excessive torque.
[0004] According to one aspect of the present invention, there is
provided a dental handpiece, comprising: a housing of a size and
configuration to be conveniently graspable by a user; a dental tool
clamping device carried by the housing; a dental tool to be clamped
in the clamping device, the dental tool being of a size and
configuration enabling it to be received in the mouth of the
patient and used for performing an operation therein involved in a
dental treatment of the patient; a rotary drive for rotating the
clamping device, and the dental tool when clamped therein; and a
transmission system coupling the rotary drive to the dental tool to
rotate same; characterized in that the dental tool includes a
driving tip for engaging the head of a fastening member to be fixed
by rotation within the patient's mouth; and in that the
transmission system includes a torque limiter for limiting the
torque applied by the rotary drive to the driving tip.
[0005] Several embodiments of the invention are described below for
purposes of example. In some described embodiments, the torque
limiter is included within the housing between the rotary drive and
the dental tool clamping device; and in other described
embodiments, the torque limiter is included within the dental tool
between its mounting shaft and the driving tip.
[0006] As will be described more particularly below, a dental
handpiece constructed in accordance with the foregoing features
enables the dentist or other dental attendant to fix fastening
members in the patient's mouth more conveniently, more speedily,
and with less risk of causing damage by excessive torque.
[0007] According to another aspect of the present invention, there
is provided, a tool for mounting to a housing including a rotary
drive, comprising: a driving tip at one end of the tool for
engaging the head of a fastening member to be fastened by rotation;
a mounting shaft at the opposite end of the tool for mounting to a
housing including a rotary drive; and a torque limiter between the
driving tip and the mounting shaft for limiting the torque to be
applied by the rotary drive to the driving tip.
[0008] According to yet another aspect of the present invention,
there is provided a dental kit comprising: a housing of a size and
configuration to be conveniently grasped by a user; a rotary drive
within the housing; a dental tool clamping device carried by the
housing and coupled to the rotary drive; and a plurality of
different dental tools selectively mountable in the dental tool
clamping device for use in various dental treatments of the
patient; at least one of the dental tools including a driving tip
for engaging the head of a fastening member to be fixed by rotation
within the patient's mouth, and a torque limiter for limiting the
torque applied by the rotary drive to the driving tip.
[0009] Further features and advantages of the invention will be
apparent from the description below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention is herein described, by way of example only,
with reference to the accompanying drawings, wherein:
[0011] FIG. 1 is a longitudinal sectional view illustrating a
dental handpiece constructed in accordance with the present
invention;
[0012] FIG. 2 is an enlarged fragmentary view of the distal end of
the handpiece of FIG. 1;
[0013] FIG. 3 is a top plan view of the proximal end of the
handpiece of FIG. 1;
[0014] FIG. 4 is an enlarged sectional view of the torque limiter
in the handpiece of FIG. 1;
[0015] FIG. 5 is a sectional view illustrating a torque applicator
tool constructed in accordance with the present invention for use
in dental handpieces;
[0016] FIG. 6 illustrates another torque applicator tool
constructed in accordance with the present invention for use in
dental handpieces;
[0017] FIG. 7 is a longitudinal sectional view illustrating a
manually driven dental handpiece constructed in accordance with the
present invention;
[0018] FIG. 8 is a view, partly in section, illustrating a dental
handpiece constructed in accordance with the present invention
driven by an external electrical motor;
[0019] FIG. 9 is a fragmentary sectional view illustrating the
proximal end of another dental handpiece constructed in accordance
with the present invention; and
[0020] FIG. 10 is a sectional view illustrating a torsion bar
overload coupling for use in a dental handpiece in accordance with
the present invention.
[0021] It is to be understood that the foregoing drawings, and the
description below, are provided primarily for purposes of
facilitating understanding the conceptual aspects of the invention
and various possible embodiments thereof, including what is
presently considered to be a preferred embodiment. In the interest
of clarity and brevity, no attempt is made to provide more details
than necessary to enable one skilled in the art, using routine
skill and design, to understand and practice the described
invention. It is to be further understood that the embodiments
described are for purposes of example only, and that the invention
is capable of being embodied in other forms and applications than
described herein.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0022] The dental handpiece illustrated in FIG. 1 includes a
housing 2 serving at one end (the proximal end) as a handle 2a of a
size and configuration to be conveniently graspable by a user,
e.g., a dentist or other dental care attendant. The opposite,
distal end of housing 2 includes a slender neck 2a carrying a tool
clamping section, generally designated 3, to receive a dental tool
of a size and configuration enabling the dental tool to be received
in the mouth of the patient and to be used for performing an
operation therein involved in a dental treatment of the patient.
Such dental handpieces are frequently constructed, e.g., as
described in my prior U.S. Pat. No. 5,549,474, for selectively
receiving various types and sizes of dental drills or other dental
tools according to the dental operation to be performed.
[0023] The dental handpiece illustrated in FIG. 1 is a battery
operated self contained unit. It includes an electrical motor 4
driven by a battery 5 within housing 2. Motor 4 is coupled by a
transmission, generally designated 6, to drive the dental tool
carried by the clamping device 3.
[0024] In accordance with the present invention, the dental
clamping device 3 at the distal end of the housing 2 receives a
dental tool 7 having a driving tip 8 for engaging the head of a
fastening member (not shown) to be fixed by rotation within the
patient's mouth. Such a fastening member may be for example an
implant to be fixed by rotation in the patient's jawbone. Also in
accordance with the present invention, the transmission 6 between
the electrical motor drive 4 and the dental tool 7 includes a
torque limiter, generally designated 10, for limiting the torque
applied by the rotary drive to the driving tip 8.
[0025] Torque limiter 10 included in the dental handpiece
illustrated in FIG. 1 is more particularly illustrated in FIGS. 2
and 4. It includes a drive shaft 11 driven by the electrical motor
4 via section 6a of the transmission system 6, and a driven shaft
12 coupled to the dental tool 7 via another section 6b of the
transmission system. The two shafts 11, 12 are each formed with
confronting flanges 11a, 12a, respectively, carrying balls 13, 14
(FIG. 4) urged into engagement with each other by a spring 15
acting on the driven shaft 12. Thus, the force applied by spring 15
urging its ball carrying flange 12a into engagement with the ball
carrying flange 11a of the drive shaft 11 determines the maximum
torque applied by the rotary motor 4 to the driving tip 8 of the
dental tool 7, since any torque above that maximum will cause
slippage between the two flanges 11a, 12a.
[0026] As shown in FIG. 1, the axis of the slender neck portion 2b
of housing 2 forms an angle ".alpha." with respect to the axis of
the handle portion 2a, and an angle ".beta." with respect to the
tool clamping section 3. Preferably, angle .beta. is 90.degree.,
whereas angle .alpha. is slightly less than 180.degree. e.g., about
150.degree..
[0027] Torque limiter 10 is located within the distal end of handle
2a and is coupled to the electrical rotary motor 4 by transmission
section 6a, e.g., any conventional step-down transmission such as a
planetary gearing. The section 6b of the transmission 6 within neck
2b of the housing 2 includes a shaft 16 coupled at one end by bevel
gears 17 to the driven shaft 12 of the torque limiter 10 and at the
opposite end by bevel gears 18 to the dental tool 7 received within
the tool clamping section 3 of the housing.
[0028] Handle 2a carries a knob 20 which is manually rotatable in
order to preset the maximum torque to be transmitted by the torque
limiter 10 to the dental tool 7. As shown in FIG. 1, knob 20 is
manually rotatable with respect to housing 2 and is formed at its
inner end with threads 21 engageable with corresponding threads in
an inner housing 22 containing the battery 5, electric motor 4, and
section 6a of the transmission 6 within the handle 2a. The drive
shaft 11 of torque limiter 10 is coupled to transmission section 6a
within the handle 2a such that rotation of knob 20 in one direction
axially displaces the inner housing 22, together with transmission
section 6a and shaft 11 of the torque limiter, towards shaft 12 of
the torque limiter, to compress spring 15, and thereby to increase
the maximum torque capable of being transmitted by the rotary drive
motor 4 to the dental tool 7. Rotation of knob 20 in the opposite
direction moves torque limiter shaft 11 away from torque limiter
shaft 12 to decrease the force applied by spring 15, and thereby
decrease the maximum torque capable of being transmitted by the
torque limiter.
[0029] As shown in FIG. 3, knob 20 is formed with finger engaging
recesses 23 to facilitate manual rotation of the knob, and with an
indicator 24 to indicate the maximum torque presetted by the
knob.
[0030] As further shown in FIG. 3, handle 2a of the dental
handpiece includes a three position toggle switch 25 for
controlling the electrical motor drive 4. The neutral position of
switch 25 is its OFF position as indicated by indicia 25a; its left
position produces a forward drive of the electrical motor 4 to
rotate the dental tool 7 in one direction as indicated by indicia
25b; and the right position of electrical switch 25 produces a
reverse drive of the electrical motor and thereby applies a torque
to the dental tool 7 in the opposite direction as indicated by
indicia 25c.
[0031] The manner of using the dental handpiece illustrated in
FIGS. 1-4 will be apparent from the above description. Thus,
whenever a fastening member, such as an implant, is to be fixed by
rotation within the patient's mouth, dental tool 7 including the
driving tip 8 is received within the tool clamping section 3 of the
dental handpiece. For example, the tool clamping section 3 of the
dental handpiece may be of the construction as described in the
above-cited U.S. Pat. No. 5,549,474, to include a button which is
depressible in order to release the dental tool clamped therein,
and to permit dental tool 7 including the driving tip 8 to be
clamped therein. The tool 7 would thus be driven by the electrical
motor 4 via the transmission 6 and torque limiter 10 to rotate the
fastening member to be fixed within the patient's mouth.
[0032] The use of the dental handpiece for this purpose thus
enables fixing the fastening member in a more convenient and
speedier manner than the manual manner used at the present time. In
addition, the torque limiter 10 limits the torque applied by the
rotary drive to the dental tool 7, and thereby to the fastening
member engaged by the dental tool, such as to avoid the danger of
applying excessive torque and causing damage to the patient.
[0033] The maximum torque applied may be preset by rotating knob 20
as described above. Thus, rotating knob in one direction increases
the force applied by spring 15 of the torque limiter 10 to thereby
increase the maximum torque capable of being transmitted to the
dental tool; whereas rotating knob 26 in the opposite direction
decreases the force applied by the spring and thereby the maximum
torque capable of being transmitted to the dental tool.
[0034] FIG. 5 illustrates the invention implemented in the dental
tool itself to be selectively applied to the tool clamping section
3 of the dental handpiece whenever it is desired to fix by rotation
a fastening member within the patient's mouth. Such a dental tool
therefore can be one of many dental tools included in a dental kit
to be selectively applied to the dental handpiece whenever needed
for a particular dental operation.
[0035] The dental tool illustrated in FIG. 5, therein generally
designated 30, includes: a mounting shaft 31 at one end for
clamping within the tool clamping section 3 of the dental
handpiece; a driving tip 32 at the opposite end for engaging the
head of the fastening member to be fixed by rotation within the
patient's mouth; and a torque limiter 33 between the mounting shaft
and the driving tip for limiting the torque capable of being
applied to the fastening member engaged by the driving tip.
[0036] Torque limiter member 33 in the dental tool illustrated in
FIG. 5 is a bellevielle-spring type overload coupling. It includes
a drive section 33a coupled to a driven section 33b by a plurality
of balls 33c urged together by a bellevielle-spring washer 34
interposed between the driven section 33b and a threaded nut 35.
Thus, by threading nut 35 more or less with respect to the driven
section 33b, the maximum torque transmitted by torque limiter 33
can be preset as desired.
[0037] The invention can also be implemented by providing a dental
kit including a dental handpiece as described above together with
one or more torque applicator dental tools as illustrated in FIG.
5, each preset for a different torque limit and/or each providing a
different type of driving tip 32 to be selected according to the
particular dental operation to be performed. Such a kit could also
include other dental tools, such as drills of various sizes, also
selectively attachable to the tool clamping section of the dental
handpiece.
[0038] FIG. 6 illustrates the invention implemented in a torque
applicator tool therein generally designated 40 also including a
mounting shaft 41 at one end coupled to a driving tip 42 at the
opposite end by another type of torque limiter 43. In this case
torque limiter 43 includes a driving section 43a coupled to a
driven section 43b by a plurality of balls 43c which are
spring-urged by individual springs 44. The torque limiter
illustrated in FIG. 6 also includes a nut 45 which may be threaded
more or less with respect to the driven section 43b for presetting
the maximum torque capable of being transmitted.
[0039] FIG. 7 illustrates the invention implemented in a dental
handpiece having a manual drive, rather than an electrical drive,
for rotating the fastening member to be fixed by rotation within
the patient's mouth. Thus, the dental handpiece illustrated in FIG.
7 is of substantially the same construction as described above with
respect to FIGS. 1-4; and therefore to facilitate understanding,
the corresponding elements have been identified by the same
reference numerals. The dental handpiece illustrated in FIG. 7
however includes a manually rotatable knob 50 instead of the
electrical motor 4 for rotating the transmission coupled by the
torque limiter 10 to rotate the driving tip 8 for fixing the
fastening member. Thus, manually rotatable knob 50 is coupled to
the drive shaft 11 of the torque limiter 10 by means of an
elongated sleeve 51, such that drive shaft 11 of the torque limiter
is rotated manually by rotating knob 50 rather than by the
electrical motor in the embodiment of FIGS. 1-4. The dental
handpiece illustrated in FIG. 7 also includes the manually
presettable knob 20 for presetting the maximum torque capable of
being transmitted by the torque limiter in the same manner as
described above with respect to FIGS. 1-4.
[0040] FIG. 8 illustrates a dental handpiece similar to the
construction of FIG. 7 except that the inner drive shaft 51 is
coupled, not to a manually rotatable knob as in FIG. 7, but rather
to an external electrical motor 60 via a flexible drive shaft 61.
The drive shaft 61 is conveniently couplable to the dental
handpiece by quick release coupling 62.
[0041] FIG. 9 illustrates the invention implemented in a dental
handpiece which includes a light source for illuminating the
working area within the patient's mouth. Thus, as shown in FIG. 9,
the dental handpiece includes an optical fiber 70 having one end
exposed to a light source 71 and the opposite end 72 oriented to
illuminate the region of the fastening member to be fixed by
rotation by the driving bit 8. In all other respects the dental
handpiece illustrated in FIG. 9 is constructed and operates
substantially as described above with respect to FIGS. 1-4, and
therefore its various components are identified by the same
reference numerals to facilitate understanding.
[0042] FIG. 10 illustrates the invention implemented in a motor
driven dental handpiece which includes a torsion bar type overload
coupling and electrical means for interrupting the operation of the
electric motor when the torque is exceeded. The torque limiter
illustrated in FIG. 10 and therein generally designated 80,
includes a drive section 81 coupled to the motor (e.g., electrical
motor 4, FIG. 1), and a driven section 82 coupled to the dental
tool (e.g., 7, FIG. 1) to be rotated by the electrical motor. In
this case, however, the two sections 81, 82 are coupled together by
a torsion bar 83 which becomes deformed according to the torque
between the two sections 81, 82. The drive section 81 includes an
electrical contact 84 that rotates with the drive section; and the
driven section 82 also includes an electrical contact 85 that
rotates with that section. The arrangement is such that when the
transmitted torque is below the maximum value, electrical contact
85 engages electrical contact 84 to maintain the electrical power
to the motor; however, when the transmitted torque exceeds a
predetermined maximum, torsion bar 83 is deformed sufficiently to
cause its contact 85 to separate from contact 84 carried by the
drive section 81 to thereby interrupt the electrical power to the
motor.
[0043] The torsion bar torque limiter illustrated in FIG. 10 can
also be made pressetable by adjusting the axial position of
electrical contact 84 with respect to the torsion bar 83. Thus, by
presetting electrical contact 84 axially away from the driven
section 82, a smaller deformation of the torsion bar 83 will
interrupt the electrical connection between contacts 84 and 85; and
by displacing the electrical contact 84 axially towards the driven
section 82 of the torque limiter, a larger deformation of torsion
bar 83 will be required in order to cause separation of the two
electrical contacts and thereby an interruption of the electrical
power to the motor.
[0044] While the invention has been described with respect to
several preferred embodiments, it will be appreciated that these
are set forth merely for purposes of example, and that many other
variations, modifications and applications of the invention may be
made.
* * * * *